Hey guys, we just did a tutorial on setting up a Local Area Network over a CAN Bus. The tutorial uses 2 CAN shields which we make, and two Arduino UNOs. If your interested in how CAN works, you may learn a thing or two with this tutorial! Here is an image of the setup with two UNOS forming a CAN network and a third is added later on in the tutorial

Here is the link to the tutorial: http://www.jayconsystems.com/tutorial/canbus/Let me know if you have any questions!